Load data for 338-300 WSM?

[mjs3240]

I just recieved my new toy. I had a Win mod 70 in 300 WSM rebarreled with a Lija 338 barrel in 338-300 WSM. Now I need some load data. The 338 WSM holds about 6 grains less powder than the 338Win and 13 grains more powder than the 338/06. These figures are to the base of the neck. Anyone have any experience with this cartirdge?

 

[LDO]

try shortmags.org-there is data there -not very impressive from LR standpoint though-my-2-dave

 

[Brent]

My Dad has one.

What bullet and or powder did you want data on?

His is throated long for the 300gr SMK and is on a LA Rem 700, so effective case capacity is a bit more than you'd get with a SA receiver set up for a shorter throat length etc.

With a 27.5" barrel, it's every bit the equal of a 338 WM. Load data for the two is very close to the same as well.

 

[mjs3240]

Brent:
My barrel is 24". The rifle with 2.5X8 Leupold weighs 7.5 pounds. I am interested primarly in 200-225 grain bullets. I plan on using it for Dall Sheep in your great state. My brother lives in Juneau so he is my guide. The reason for the 338 is for Griz insurance. I wanted a lighter rifle than my Ruger 338 Win Mag. I am getting too old,60,to be packing 9 pounds of iron up and down the mountains. I did go to the range today and was able to get 2885 fps with the 200 Nosler Ballistic tip and 70 grains of RL 19. Accurcary was not too good though, around 2" at 100 yards. This is the first time I have fired the rifle. As far as powder goes I will buy whatever seems to work. I have 4064,4320, varget H4350 H4895 W748 and RL 19.
MJS

 

[Brent]

Let me get his suggestion on loads and I'll post a bit later this eve when I'm at his place. He keeps buggin me to pick him up more 225 Accubonds all the time, so they must be shooting pretty good I assume.

 

[wapiti13]

MJS,
I used to shoot a 338/06 AI. Have several friends that live by 338s. You might want to try the new 185 gr Barnes TSX. You don't need bullet weight with an X bullet. Have shot several elk & deer with the regular 185 gr X and have blown out both sides on everything shot. The extra velocity you could get with the 185 could help your trajectory and not have to seat as deep in your WSM case. Another powder that works great in your rifle could be Vit N550. I think you'll need the slightly faster version than N560 which works great in the 300 WSM. Also, check your case capacity full of water in grains & then compare to other cases. A more accurate comparison.

 

[Brent]

All loads use:
H4831SC
215M
338 caliber insert was used in a Stoney Point comparetor to reference OAL to ogive rather than the bullet tip.

215 SGK (shot almost as good as 225 Accubond)
75gr


225gr Accubond (1" at 300 yards, a real good load)
74.5 gr
2.5" OAL (ogive)
2.590 (to ogive) at land contact
.090" off lands
2900 fps (bbl @ 24")

225gr Barnes TSX (3/4" at 200 yards, but not when seated near the lands though.)
74.5 gr
2.5" OAL (to ogive)
2.618 (ogive) at land contact
.116" off lands
2900 fps (bbl @ 24")


250 SGK, SMK, Lapua Scenar - (Speer Grand Slam sucked) SGK and SMK were the best 250's.
72.0 gr
2700+ fps (bbl @ 25")


300 SMK (This and the Accubond shoot about the same, and are about the best loads of all)
64.5 gr
2.542 (to ogive) 3.285" OAL (to tip)
2.562 (to ogive) at land contact
.020 off lands
2450 fps (bbl @ 27.5") (2400 fps - bbl @ 24".... go figure)

<font color="red"> Keep in mind, the throat for this chamber may be much longer (throated for the 300 gr SMK) than one throated for 225-250 gr bullets, so your pressure may run higher with these loads and MV's.</font>

 

[mjs3240]

Brent
Thanks for the data. This is my first true wildcat rifle and I am enjoying working with it.
MJS /ubbthreads/images/graemlins/smile.gif

 

[Kevin]

Brent,
Could you give me a good guess what the velocity may be out of a 15.5 inch barrel with the 300gr.